Biaxially expanded polymer film, tufted carpet comprising it and method for their manufacture

Abstract

The invention relates to a self-supporting polymer film, to a process for preparing said self-supporting polymer film, to a hot-melt adhesive, to uses of a self-supporting polymer film, to a method for preparing an assembly of at least two objects, and to a tufted carpet. The self-supporting polymer film of the invention comprises a continuous layer of a thermoplastic composition comprising a thermoplastic polymer, wherein the composition has a melt flow index (MFI) of 100 g/10 minutes or more, and wherein the polymer film is biaxially expanded.

1 . A self-supporting polymer film comprising a continuous layer of a thermoplastic composition comprising a thermoplastic polymer, said thermoplastic composition having a melt flow index (MFI) of 100 g/10 minutes or more, wherein said polymer film is biaxially expanded. 
     
     
         2 . A self-supporting polymer film according to  claim 1 , wherein said thermoplastic composition has a MFI of 300-500 g/10 minutes. 
     
     
         3 . A self-supporting polymer film according to  claim 1  or  2 , wherein said thermoplastic composition has a MFI of 400-500 g/10 minutes. 
     
     
         4 . A self-supporting polymer film according to any one of  claims 1 - 3 , wherein said layer has a thickness of 500 μm or less. 
     
     
         5 . A self-supporting polymer film according to any one of  claims 1 - 4 , wherein said layer has a thickness of 100 μm or less. 
     
     
         6 . A self-supporting polymer film according to any one of  claims 1 - 5 , wherein said composition comprises an infrared absorption agent. 
     
     
         7 . A self-supporting polymer film according to any one of  claims 1 - 6 , wherein said thermoplastic polymer comprises one or more selected from the group consisting of ethylene-vinyl acetate co-polymers, ethylene-acrylate polymer, polyolefins, polyamides, polyesters and polyurethanes. 
     
     
         8 . A self-supporting polymer film according to any one of  claims 1 - 7 , wherein said thermoplastic polymer comprises at least two different polymer selected from the group consisting of ethylene-vinyl acetate co-polymers, ethylene-acrylate polymer, polyolefins, polyamides, polyesters and polyurethanes. 
     
     
         9 . A self-supporting polymer film according to any one of  claims 1 - 8 , wherein said thermoplastic polymer comprises ethylene-vinyl acetate co-polymer. 
     
     
         10 . A self-supporting polymer film according to any one of  claims 1 - 9 , wherein said thermoplastic composition further comprises one or more waxes. 
     
     
         11 . Process for preparing a self-supporting polymer film according to any one of  claims 1 - 10 , comprising blow film extruding a tubular film from a melt of at least said thermoplastic composition. 
     
     
         12 . Process according to  claim 11 , wherein the film is blown at a temperature of 50-100° C. 
     
     
         13 . Process according to  claim 11  or  12 , wherein the film is blown at a temperature of 60-78° C. 
     
     
         14 . Process according to any one of  claims 11 - 13 , wherein said self-supporting polymer film is a multilayer film, and wherein said process comprises simultaneous extruding of two or more materials through a single die. 
     
     
         15 . A hot-melt adhesive comprising a self-supporting polymer film according to any one of  claims 1 - 10 . 
     
     
         16 . A hot-melt adhesive according to  claim 15 , wherein said hot-melt adhesive is a multilayer film having two exposed outer layers, wherein one or both of said exposed outer layers comprises said thermoplastic composition. 
     
     
         17 . Use of a polymer film according to any one of  claims 1 - 10  as hot-melt adhesive. 
     
     
         18 . Use according to  claim 17 , wherein the hot-melt adhesive is applied as part of a back-coat of a tufted carpet. 
     
     
         19 . Use according to  claim 17  or  18 , wherein the hot-melt adhesive is applied in the manufacturing of artificial turf. 
     
     
         20 . A method for preparing an assembly of at least two objects, said process comprising contacting a hot-melt adhesive according to  claim 15  or  16  to at least a first object and a second object, increasing the temperature of the hot-melt adhesive to above the activation temperature of the hot-melt adhesive (TA) and, in contact with at least said first and second object, decreasing the temperature of the hot-melt adhesive to below the activation temperature. 
     
     
         21 . Method according to  claim 20 , comprising pre-heating said first and/or second object prior to applying said hot-melt adhesive. 
     
     
         22 . Method according to  claim 20  or  21 , wherein said first object and/or said second object comprise a fibrous material, such as textile. 
     
     
         23 . Process for manufacturing a tufted carpet, comprising anchoring tufted yarn and/or fibres to a primary backing of the carpet by a method according to claim any one of  claims 20 - 22 . 
     
     
         24 . Process according to  claim 23 , comprising using a hot-melt adhesive according to  claim 15  or  16  for locking the tufted yarn and/or fibres in a primary backing of the carpet. 
     
     
         25 . Tufted carpet comprising a primary backing stitched with loops of yarn to form a tufted structure projecting outwardly from said primary backing; a layer of hot-melt adhesive according to  claim 15  or  16 , attached to the primary backing; and a secondary backing affixed to the hot-melt adhesive layer.